Using a point in a bash script

Question

What does the dot on line 8 of the next code snippet mean from the source /etc/profilein the Mac OS X Mavericks terminal.

  1 # System-wide .profile for sh(1)
  2 
  3 if [ -x /usr/libexec/path_helper ]; then
  4         eval `/usr/libexec/path_helper -s`
  5 fi
  6 
  7 if [ "${BASH-no}" != "no" ]; then
  8         [ -r /etc/bashrc ] && . /etc/bashrc
  9 fi

Answer 1

In bash, .this is another way to spell source. So this line is the same:

# System-wide .profile for sh(1)

if [ -x /usr/libexec/path_helper ]; then
        eval `/usr/libexec/path_helper -s`
fi

if [ "${BASH-no}" != "no" ]; then
        [ -r /etc/bashrc ] && source /etc/bashrc
fi

sourceinterprets the file as if the contents were included in the command location source. The difference with doing this is that it can set aliasor define functionor variables.

Answer 2

According to Bash HOWTO Request :

( . filename ), , . , , .